Pump



March 26, 1968 J. s. MARSH 3,374,748

PUMP

Filed May 27, 1966 lNveN-rolz Hama/wmf# ATTORNEYS fw United States Patent Office 3,374,748 Patented Mar. 26, 1968 3,374,748 PUMP This invention relates to a positive displacement rotary pump of the gear within a gear type, with multiple pumping elements in a single casing driven by a single shaft. The gear within a gear or internal gear type pump has long been known and used for pumping liuids, and is generally illustrated in U.S. Patent No. 3,152,551.

The principal object of the invention i's to provide multiple pumping elements of the gear within a gear type in a single casing, with the elements driven by a single shaft.

A further object of the invention is to provide such multiple pumping elements in a casing which may be ported in a variety of ways on the suction and discharge sides of the pump, As will be pointed out in detail hereafter, the ports may be arranged so that the pump may feed separate fluid lines from a common source, or may act as a mixer or blender by drawing from separate feed lines and discharging through a single port.

A preferred embodiment of the invention is shown in the drawing, in which:

FIGURE 1 is a perspective view of the pump with a portion of the casing cut away to show the internal elements;

FIGURE 2 is a perspective, blow-apart view of two rotors and the head or cover plate carrying the idler pin, cresecent and divider plate.

The embodiment depicted in the drawing shows two pumping elements. However, more than two pumping elements may be incorporated if desired.

In the drawing, the housing or casing is shown at and is supported on base 12. A drive shaft 14 (driven by motor not shown) is journaled in the casing in sleeve bearing 16 and sealed by stuffing box 18 and packing gland 20.

Adjacent the bearing 16, the housing 10 enlarges into a barrel configuration to form a pumping chamber. A portion of the shaft 14 extends beyond the bearing into the pump chamber. Fixed on this extension of the shaft 14 is a rotor 22 with teeth 24. Mounted on teeth 24 is rotor ring 26 with teeth 28. The ring 26 is fixed to teeth 24 by capscrews 30, and thus, the ring is driven by the rotor 22 and the shaft 14. The end of the barrelshaped casing opposite the drive shaft 14 has a cylindrical opening through which the drive shaft and rotors are placed within the casing. This opening is closed by a head or cover plate 32 which is attached to the casing 10 by screws 34 inserted through screw holes 36 in the head. Mounted on the head 32 is a stub shaft or pin 38 which extends axially into the pump chamber eccentrically to the drive shaft 14. The stub shaft 38 forms a journal for idler gears 40 and 42 which are mounted on the stub shaft on each side of the divider plate 44. This plate is fixed by set screw 46 on the stub shaft. By means of the eccentric alignment of the idler gears and the rotors, a portion of the teeth of idler gear 40 meshes with a portion of the teeth of rotor 22. Likewise, a portion of the teeth of idler gear 44 meshes with the teeth of rotor ring 26. The driven rotors thus drive the idler gears. The upper section of divider plate 44 has an arcuate periphery and is of such width as to align and seal with the Width of the continuous ring portion of the rotor ring 26. The divider plate divides the pump chamber into two compartments, each having a pumping element therein.

A crescent shaped projection 48, formed integrally with the head 32, extends into the pump chamber in the space between the rotor teeth and the idler-gear teeth. The end face of the crescent is in close proximity to the inside face of the rotor 22. The periphery of the lower portion of the divider plate 44 is arcuate in shape and extends to the concave face of the crescent 48.

The casing 10 has a port 50, which is the single suction port when the drive shaft 14 isturned clockwise as viewed from the right in FIGURE 1. Ports 52 and 54 are discharge ports when the drive shaft is turned clockwise as stated. It will be noted that the casing area between the discharge ports aligns and seals with the continuous ring portion of the rotor ring 26 and divider plate 44.

In operation, with the drive shaft 14 turning clockwise as viewed from the right in FIGURE 1, the shaft 14 drives rotor 22 and rotor ring 26. The two rotors, in turn, drive idler gears 40 and 42. This causes a suction in port 50 and draws fluid into the open spaces between the teeth of the rotors and idler gears. The fluid is moved to the outlet ports 52 and 54, and discharged under pressure through these ports. The sections of the vcasing on each side of divider plate 44 form separate passageways or chambers. The inlet port 50 feeds into both chambers. The outlet ports 52 and 54 discharge separately from each chamber.

If the rotation of the shaft 14 is reversed, that is, operated counter-clockwise as viewed from the right in FIG- URE 1, the separate ports 52 and 54 become suction ports and port 50 becomes a common discharge port. Such an operation may be used to blend or mix fluids from two sources.

More than two pumping elements may be incorporated into such a pump if desired, and the capacities of the various elements may be varied by changes in the length of the teeth of the rotor and the width of the teeth of the idler gears.

Porting arrangements, both internal and external, may be varied to meet the requirements of particular applications of the pump. For example, the device may be ported in the various ways stated below:

(l) Multiple suction and discharge ports.

(2) Single suction and multiple -discharge ports.

( 3) Single discharge and multiple suction ports.

(4) Single suction and discharge ports common to each pumping element.

(5) Single external suction and discharge ports with staged internal porting.

The various porting arrangements which can be obtained with my pump offer substantial advantages. For example, through a single pump, oil can be fed from a single reservoir to separate bearings- Also, different fluids from separate reservoirs may be blended in a single pump and vfed to a single delivery point.

An advantage of my multiple pumping elements in a single casing with a single drive shaft is the obtaining of a higher capacity at a given speed. Also, desired capacity can be maintained with reduced rim Aspeed and smaller diameter rotors.

In addition, the support for the idler pin provided by the divider plate 44 reduces deflection problems encountered in long idler pin designs.

I claim:

1. In a reversible pump of the internal gear type, the combination rcomprising (l) a housing,

(2) a rotor gear journaled in the housing,

(3) means Vfor driving said rotor gear,

(4) a toothed Vrotor rin-g fixed on the teeth of said rotor gear, theY teeth' of the ring forming extensions of the teeth of the rotor gear,

(5) a head forming a cover plate for said housing,

(6) 'an idler pin extending within said housing, from said head, and eccentrically mounted with respect to the toothed rotor,

(7) a divider plate mounted on said idler pin,

(8) idler gears mounted on said idler pin on each side of said divider plate, one of said idler gears being adapted to intermesh vwith teeth of said rotor gear and the other idler gear being adapted to intermesh with teeth of said rotor ring,

' (9) va crescent-shaped projection extending from said head into the space between said rotors and said idler gears, and

(10) ports in said housing providing uid inlet and outlet means.

2. In a multiple passage reversible pump of the internal gear type, the combination comprising (1) a pump housing,

(2) a toothed rotor positioned Within said housing and 4 Y head and eccentrically mounted with respect to said rotor, 1 Y

(6) a divider plate fixed on said pin,

(7) idler gears mounted on said pin on each side of said divider plate, teeth of said idlers intermeshing with teeth of said rotor,

(8) a crescent-shaped projection extending from said head into the space between said rotor and said idler gears, and

(9) ports in said housing providing uid inlet and outlet means.

References Cited UNITED sTATEs PATENTS 892,295 6/ 1908 Nutz 91-68 1,596,737 6/1924 Petersen 103-126 1,545,204 7/1925 Schirmer 103-126 1,724,008 8/1929 Dinesen 103-126 1,802,527 4/1931 Nichols 103-126 2,740,386 4/1956 Crandall 123-12 3,152,551 10/1964 YPeters 103-126 3,224,198 12/1965 Schimkat 103-126 3,306,531 2/1967 Oppermann 230-141 DONLEY I. STOCKING, Primary Examiner.

W. I. GOODLIN, Assistant Examiner. 

1. IN A REVERSIBLE PUMP OF THE INTERNAL GEAR TYPE, THE COMBINATION COMPRISING (1) A HOUSING, (2) A ROTOR GEAR JOURNALED IN THE HOUSING, (3) MEANS FOR DRIVING SAID ROTOR GEAR, (4) A TOOTHED ROTOR RING FIXED ON THE TEETH OF SAID ROTOR GEAR, THE TEETH OF THE RING FORMING EXTENSIONS OF THE TEETH OF THE ROTOR GEAR, (5) A HEAD FORMING A COVER PLATE FOR SAID HOUSING, (6) AN IDLER PIN EXTENDING WITHIN SAID HOUSING, FROM SAID HEAD, AND ECCENTRICALLY MOUNTED WITH RESPECT TO THE TOOTHED ROTOR, (7) A DIVIDER PLATE MOUNTED ON SAID IDLER PIN, (8) IDLER GEARS MOUNTED ON SAID IDLER PIN ON EACH SIDE OF SAID DIVIDER PLATE, ONE OF SAID IDLER GEARS 